Line data    Source code

       1             : /* Find source location for PC address in module.
       2             :    Copyright (C) 2005, 2008, 2014 Red Hat, Inc.
       3             :    This file is part of elfutils.
       4             : 
       5             :    This file is free software; you can redistribute it and/or modify
       6             :    it under the terms of either
       7             : 
       8             :      * the GNU Lesser General Public License as published by the Free
       9             :        Software Foundation; either version 3 of the License, or (at
      10             :        your option) any later version
      11             : 
      12             :    or
      13             : 
      14             :      * the GNU General Public License as published by the Free
      15             :        Software Foundation; either version 2 of the License, or (at
      16             :        your option) any later version
      17             : 
      18             :    or both in parallel, as here.
      19             : 
      20             :    elfutils is distributed in the hope that it will be useful, but
      21             :    WITHOUT ANY WARRANTY; without even the implied warranty of
      22             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      23             :    General Public License for more details.
      24             : 
      25             :    You should have received copies of the GNU General Public License and
      26             :    the GNU Lesser General Public License along with this program.  If
      27             :    not, see <http://www.gnu.org/licenses/>.  */
      28             : 
      29             : #ifdef HAVE_CONFIG_H
      30             : # include <config.h>
      31             : #endif
      32             : 
      33             : #include "libdwflP.h"
      34             : #include "../libdw/libdwP.h"
      35             : 
      36             : Dwfl_Line *
      37         233 : dwfl_module_getsrc (Dwfl_Module *mod, Dwarf_Addr addr)
      38             : {
      39         233 :   Dwarf_Addr bias;
      40         233 :   if (INTUSE(dwfl_module_getdwarf) (mod, &bias) == NULL)
      41             :     return NULL;
      42             : 
      43         163 :   struct dwfl_cu *cu;
      44         163 :   Dwfl_Error error = __libdwfl_addrcu (mod, addr, &cu);
      45         163 :   if (likely (error == DWFL_E_NOERROR))
      46         155 :     error = __libdwfl_cu_getsrclines (cu);
      47         163 :   if (likely (error == DWFL_E_NOERROR))
      48             :     {
      49         155 :       Dwarf_Lines *lines = cu->die.cu->lines;
      50         155 :       size_t nlines = lines->nlines;
      51         155 :       if (nlines > 0)
      52             :         {
      53             :           /* This is guaranteed for us by libdw read_srclines.  */
      54         155 :           assert(lines->info[nlines - 1].end_sequence);
      55             : 
      56             :           /* Now we look at the module-relative address.  */
      57         155 :           addr -= bias;
      58             : 
      59             :           /* The lines are sorted by address, so we can use binary search.  */
      60         155 :           size_t l = 0, u = nlines - 1;
      61         817 :           while (l < u)
      62             :             {
      63         507 :               size_t idx = u - (u - l) / 2;
      64         507 :               Dwarf_Line *line = &lines->info[idx];
      65         507 :               if (addr < line->addr)
      66         286 :                 u = idx - 1;
      67             :               else
      68             :                 l = idx;
      69             :             }
      70             : 
      71             :           /* The last line which is less than or equal to addr is what
      72             :              we want, unless it is the end_sequence which is after the
      73             :              current line sequence.  */
      74         155 :           Dwarf_Line *line = &lines->info[l];
      75         155 :           if (! line->end_sequence && line->addr <= addr)
      76         155 :             return &cu->lines->idx[l];
      77             :         }
      78             : 
      79             :       error = DWFL_E_ADDR_OUTOFRANGE;
      80             :     }
      81             : 
      82           8 :   __libdwfl_seterrno (error);
      83           8 :   return NULL;
      84             : }
      85             : INTDEF (dwfl_module_getsrc)